Multiple-roller bearing unit



J. M. DUCHARME MULTIPLE- ROLLER BEARING UNIT mr., 2, R950 Filed Jan. 27, 1948 Patented Nov. 28, 1950 UNITED STATES PATENT OFFICE.

MULTIPLE-ROLLER BEARING UNIT Jean M. Ducharme, East Walpole, Mass., assigner to Crandall Dry Dock Engineers Inc., Cambridge, Mass., a corporationrof Massachusetts Application January 27, 1948, Serial No. 4,686

4 Claims.

supporting tracks and a body which is to be moved along the tracks, or between such supporting tracks and generally parallel runners of one or more cars or trucks which may carry the body which is to be moved along the tracks, such as a ship or hull being moved to or from a body of water, or from place to place in a railway drydocking facility.

Multiple-roller units of the general type to which the invention relates are made in various lengths to suit the requirements of dilerent operations in any particular dry-docking facility. For example, at more or less level regions of a dry-docking facility, relatively short units having but five or six rollers in each unit conveniently are useable in tandem for supporting a cradled hull in the process of construction, or undergoing overhauling. Such hulls are more readily shiftable from place to place on the short roller units than would `be the case with longer units, and the short units need no endwise con-- nection together, which enables removal of units as they become free of the load and their replacement forward of the moving load.

On the other hand, it is preferable to employ relatively long roller units, mechanically connected together in tandem, on the railway tracks leading to `and from a body of water inasmuch as these tracks may have substantial inclination requiring endwise connection of the units so that units in advance of a load moving down the ineline will not run away, and so that units in rear of a load moving up the incline will be maintained against running away.

Heretofore, the rollers of these roller bearing units have been mounted in carrier frames which have had parallel side bars of wood, or angle iron side bars with wooden bar llers. In the case of the all-Wood side bars, the rollers customarily have been rotatably mounted on axially extending shafts whose ends have had bearings directly ih the Wooden side bars. While these shafts serve primarily for maintaining the rollers in predetermined spaced parallelism, and are relatively free of any load which is being transported on the rollers, the heavy loads which are required to be carried by such roller units do impose stresses on the shafts which gradually enlarge and distort the holes in the wood sidebars in which the shaft ends are mounted, so that the" rollers can depart from their desired parallelism with each other which deleteriously affects the desired free rolling action of the rollers. Correction of this fault involves replacement of the entire side bars by new ones.

The prior composite angle iron and wood sid members for such multiple-roller bearing units represent an attempt to prolong the eiective useful life of the units. Where these composite metal and wood side members have been employed, it has been usual to form the rollers with integral end pintles, and these pintles have been mounted in holes in the angle iron bars with substantial extent also into the wooden filler bars. In this case, each roller and its pintles rotate as a unit, and the rotating pintles gradually enlarge and distort the holes in the side members with results comparable to those described in connection with the all-wood side bars, including the need to replace entire composite side members in order to correct the fault. Also, the engagement of metal on metal gradually wears an annular groove in each pintle, which. further aggravates the looseness of the rollers in their carrier frame.

It is among the objects of my present invention to provide multiple-roller bearing units wherein the individual rcllers have end pintles mounted in retainers which are readily insertible in and removable from the side bars of the rollercarrying frames of the units. I provide a pintle retainer insert of suitable material which quickly may be inserted in a hole or socket of a carrier frameside bar to provide a substantial length of surface engagement for a roller pintle engaged therein, and having means coacting with the bar` to prevent rotation of the insert relative to the bar.

Another object is to provide a multiple-roller bearing unit having a roller-carrying frame including generally parallel side bars between which the rollers are arranged transversely of the frame in spaced parallelism, each roller having integral end pintles and each pintle being engaged, substantially throughout its extent, in an insert retainer element which is non-rotatably associated with a side bar of the frame and which is maintained in its said non-rotatable association with the bar by an end portion of the roller whose pintle is engaged therein.

Yet another object is to provide a retainer element for an end pintle of a roller in a carrier frame, said element being readily insertible in of a multiple-roller bearing unit embodying 'features of the invention;

Fig. 2 is an edge elevation Aof Aa `portion of the unit represented in Fig. l;

Fig. 3 is a cross-sectional view on line 3 3 of Fig. 1, on a larger scale, but showing the roller and its pintle in elevation; and

Fig. 4 fis a vcross-sectional view on line 4 4 of Fig. 3.

.Referring tothe drawing, the particular embodirnent or" the invention as illustrated has a, roller-carrying frame consisting of twoangle iron side members at@ and l2 maintained in spaced general parallelism by thecross braces Ul against whose opposite ends the side members I0, I2 are rigidly secured by the-bolts Iii. The bolts extend through Va wall of each side member and lengthwise through the respective cross-braces, with the :head of veach 'bolt engaging one side men-1- loer-and a nut 'i8 screwed onthe other endof each bolt into engagement with the other side member.

The rollers 29 Vmay be of a usual type, each having an annular flange 2E at each end of the roller proper, andv veach having an integral pintle 24 extending axially outward beyond each flange 2.2.

4According' to the invention, however, the roller pintles 24 are not mounted directly in the lside members of the frame, as has been customary heretofore, butextend each into its own retainer element 2e which in turn is supported by a side member Iii. or |12.

As best seen in Figs. 3 and e, each retainer element 5251 has integrally formed thereon, at one end, a head portion 23 of larger external` diameter than lthe main body or" the retainer, and this headportion '28 has a lateral extension 3i] which terminates in a foot 32.

:Before 'the roller-carrying frame is assembled intoits inal rigid vform, the retainerl elements 26 areinserted 'each into one of a series of holes 34- which are suitably7 spaced apart along each side member i9 and i2'. Each of' the elements 2i?` has its headl 28 on that side of its side member which will be innermost in the assembled frame, and each is positioned on its side member withvlitsfoot-32' engaged over an edge margin oi-*thef'sidemember whereby each element is positivelyr restrained against rotation in its side member. When-all of the retainer elements are in -place on the respective side members, the

pihtlesl -2'4'at Vone end of all of the rollers may bey inserted fone into each retainer element of one Vside member, followed by similar insertion oilth'e-pintles Vatthe other end of the rollers into theretainer elements of the otherV side member', after which the side members may be secured byv the bolts it against the opposite ends of the cross-braces |42 As shown in the drawing, e'ac'h'of' the-*angle iron side members has one wall NV disposed in avertical plane and'has its other Wall i0 extending outward, in a horizontal plane, from the upper end of the wall I0. The holes 34 extend through the wall IU of each side member, the number and spacing of the holes in each side member agreeing with the number and spacing of rollers to be mounted in any particular frame. The retainer elements 26 preferably A,have their body portions formed with slight external taper, as shown, to facilitate their insertion in holes 34, and each element, as it is being inserted, is held with the foot 32 of its projection :in position to engage over the inner margin of wall l of the side member, as clearly seen in Fig. 3, where the head 28 of the retainer element is shown seated against wall ID',

-with the adjacent body portion of the element y nicely tting the hole 3d in which the element is held against rotation by the foot 32.

After the rollers have been mounted as described, and the carrier frame made rigid, the multiple-roller bearing unit is ready for service, with the outer shoulders 23 of the ange portions of the rollers in positions to maintain theretainer elements against any appreciable inward movementaxially of the respective rollers. However, slight clearance is provided between the shoulders23- and the retainer elements when the latter are fullyA seated.

Itw-ill be obfv-ious from the foregoing description, in connection with the drawing, that I have pr'ovided eectively durablek and encient retainers for the individual rollers of a multiple-roller bearing unit, and have eliminated the need for combining wooden iiller mem-bers with angle iron side members as has been considered requisite in the prior' as the replaceable inserts take such wear as may.'

be :ineidentto stresses and friction at the pintle regions.

I claim as-niyl invention:

l. A multiple-roller bearing unit for railwaydry-docks, comprising a roller-carrying frame adapted to be supported on a single rail of the railway with the rollers: resting on the rail and with a'hull resting on the rollers whereby thehull may Vbe movedV along the railway with simultaneous movement of the roller-carrying frame'v in the same direction 4but at one-half the rate ofvtravel ofthe hull, said frame having a plurality of generally parallel side members, and means extending transversely between the side members connecting them rigidly together in spaced relation, each said side member having a series vof spaced holes'thereinfopen toward the other side member, and said holes being axially aligned 'in the two side members, a series of rollers, each extending Ytransversely between the side mem-bersA and each having a-pintle at each end, a retainer element for-each of said roller pintles, each said retainer -element having a body portion inserted in a saidv hole in a side member, and each said body portion having an axial hole therein within which a said pintle has substantial extent, and rigid means extending radially outward from said body portion of `each retainer element in va plane generally'parallel to theY adjacent end of a saidV roller and having a relatively broad foot engaged over an edge of a said side member for preventing relative rotation of the retainer elements and said side members, the ends of the rollers coacting with said radially extending means to maintain the said feet in engagement over the edges of the side members.

2. A multiple-roller bearing unit for railway dry-docks, comprising a roller-carrying frame adapted to be supported on a single rail of the railway with the rollers resting on the rail and with a hull resting on the rollers whereby the hull may be moved along the railway with simultaneous movement of the roller-carrying frame in the same direction but at one-half the rate of travel of the hull, said frame having a plurality oi generally parallel side members, and means extending transversely between the side members connecting them rigidly together in spaced relation, each said side member having a series of spaced holes therein open toward" the other side member, and said holes being axially aligned in the two side members, a series of rollers, each having a body portion, and each having an integral pintle projecting axially at each end of the roller body portion, a retainer element for each said pintle and seated respectively in said holes in the side members, each retainer element having a head portion intervening between a side member and an end of a roller body portion, and each said head portion of a retainer element having a radial projection thereon terminating in an angular foot, engaging over an edge portion of a side member, for maintaining the retainer element against rotation in the side member, the ends of the rollers coacting with said head por-W tions of the retainer elements to maintain said angular feet in engagement over said edge portions of the side members.

3. A multiple-roller bearing unit for railway dry-docks, comprising a roller-carrying frame adapted to be supported on a single rail of the railway with the rollers resting on the rail and with a hull resting on the rollers whereby the hull may be moved along the railway with simultaneous movement of the roller-carrying frame in the same direction but at one-half the rate of travel of the hull, said frame having a plurality of generally parallel side members, and means extending transversely between the side members connecting them rigidly together in spaced relation, each said side member having a series of spaced holes therein open toward the other side member, and said holes being axially aligned in the two side members, a series of rollers, each having a body portion, and each having an integral pintle projecting axially at each end of and a body portion inserted in a said hole in a side member, and means on the head of each retainer element extending radially outward between a side member and the adjacent end of a roller and having relatively broad engagement with a side member outward of said body portion of a retainer element thereby to prevent relative rotation of the retainer element and side member, the ends of the rollers maintaining said radially extending means in engagement with the side members.

fl. In a multipleroller bearing unit for railway dry-docks, a frame with a multiplicity of rollers mounted therein adapted to be supporte-d on a single rail of the railway with the rollers resting on the rail and with a hull resting on the rollers whereby the hull may be moved along the railway with simultaneous movement of the rollcarrying frame in the same direction but at onehalf the rate oic travel of the hull, an insert retainer element for each end of each roller, said frame having generally parallel side members, and there being spaced holes in the side members, each said retainer element having a body portion inserted in one of said holes and seated on the walls thereof, and each having a head end portion intervening between a side member and a body portion ci the roller whereby the retainer element is restrained against any appreciable axial movement, and means on each retainer element extending radially outward from said head end portion of the retainer element with an angular foot portion engaged over an edge of a side member, whereby said radially extending means and said feet stabilize the retainer elements in the side members and prevent their rotation in the side members.

JEAN M. DUCHARME.

REFERENCES CITED The following references are oi record in the file of this patent:

'UNITED STATES PATENTS Number Name Date 714,432 Alvey Nov. 25, 1902 855,903 Packer June 4, 1907 867,350 Dehler Oct. 1, 1907 1,136,089 Bernheim Apr. 20, 1915 2,107,822 Hahn Feb. 8, 1938 2,392,081 Crandall Jan. 1, 1946 

